jhusafa61

My 1999 ES 300 will not shift into overdrive.
Had problems with O2 sensors and didn't get it fixed. Now overdrive doesn't work
Code 325 and 330 and 171.
Anyone else have similar problems?

tomf

My guess is to why you don't have overdrive is because of the errors you are getting. Based on the codes you may have two different problems. P0171 could be related to the O2 sensor or the MAF. The other two codes relate to the knock sensors. When knock sensor codes are detected one of the things the ECM does is put the car in limp mode which limits the ability of the car to be driven aggressively. It doesn't let you go into overdrive to protect the engine.

So if you previously had problems with O2 sensor that you did not correct, I'd take care of that problem first and see if that doesn't solve all your problems. Then work on the knock if those codes persist.

If you want overdrive you are going to have to take care of your car's malfunctions.

These are common problems and there are plenty of threads detailing how to fix them.

jhusafa61

TOMF
Thanks for your insight.
Took car to local Toyota dealer, who worked on MAF, then replaced knock sensors.
Car worked fine for 70 miles, then got VSC , VSC off light and Check Engine light. i.e O2 Sensors.
When will I ever learn not to trust dealer mechanics.